The present invention relates to grinding machines and more particularly to the liquid spraying of the grinding wheel.
The spraying of a grinding wheel with a liquid always results in a projection and splashing of liquid and, in some cases, in the formation of mist. The volume and the direction of such liquid projection and the formation of the mist are functions of various parameters, among which the most important are the position and the rate of flow of the spraying liquid and the speed of the grinding wheel.
In most cases, the grinding wheel is surrounded by a housing which receives and canalizes the projected liquid toward a recovering or eliminating tank.
In grinding machines in which the grinding wheel rotates at high speed employed for work of precision requiring a constant supervision of the work piece to be ground, the liquid splashing and the mist may considerably hinder the observation of this work piece.
Some devices are known which are designed to prevent an irregular dispersion of the liquid splashes and, for example, comprise sets of fins which are disposed in the housing on the downstream side of the work piece to be ground, so as to prevent the drops of liquid from rebounding by breaking their trajectory and collecting them and subsequently allowing the liquid to flow under the effect of gravity into a collecting tank. Generally, these fins have a relatively complicated configuration and their arrangement in the housing, to which they are secured, is such that the fins collect and retain a large part of the liquid with particles of material which are deposited therein and finally soil the arrangement. Such soiling requires taking down the housing for cleaning and scraping the fins.
French Patent o. 2,557,000 discloses in particular an arrangement of this type in the application thereof in a machine for grinding ophthalmic glasses. In this disclosed device, fins are provided which are secured to the inner surface of the housing and each fin has a curved cross-sectional shape and, when viewed in plan, a shape bent at an obtuse angle however, in this device, the particles of material detached by the grinding wheel accumulate in the corners formed between the wall of the housing and the curved fins and in the fins.